With gas turbines, especially for automotive plants, considerable variations with respect to angular direction, as well as to velocity will occur in the gas flow during various operating conditions. On occasions, supersonic velocities will occur, which imposes considerable loads upon the individual guide vanes in the stator portion, as well as upon the vane grid as a unit, and will involve problems in matching the components, when one flow directing member receives the flow leaving a preceeding member.
With a conventional, automotive gas turbine plant having a separate power turbine rotor, the latter will not, during starting and acceleration of the vehicle, or during idling with a stationary vehicle, transform the gas flowing through the rotor into work. The gas will therefore, especially during stall and full throttle, leave the power turbine rotor vanes with a velocity, considerably higher than that attained during normal operating conditions, and simultaneously with a high degree of rotation and consequent losses. It is therefore necessary to design the leading edge of the individual guide vane in such a manner that the vane, on the one hand, can withstand temperature strains and vibrations, and, on the other hand can take care of the gas flow in an efficient manner.